Certain mechanical heart assist device systems include vessel deforming components in the form of inflatable balloons or chambers which form part of implantable counter-pulsation heart assist devices. In certain specific embodiments, the vessel deforming components are cyclically inflated and deflated and used to compress the patient's ascending aorta during diastole and release the compression during systole, thereby assisting with pushing blood to the patient's body.
The balloon or chamber are generally secured to the aorta (or other blood vessel) by a substantially flexible, non-elastic, non-distensible wrap or sheath, which is secured around a section of the aorta with the balloon or chamber therebetween. For the heart assist device to function efficiently, it is necessary that the wrap be a snug fit around the aorta when the balloon or chamber is deflated.
In use, the securing of the balloon to the aorta with the wrap can be awkward or difficult. That is, it can be difficult to position a wrap around the aorta during surgery for various reasons, including the fact that wrap is made of a flexible material that is not easily directed around and between various organs and vessels in the chest cavity. An additional complication can arise based on the size of the patient's aorta—the variance in aorta size depending on the patient can result in a situation in which the wrap is not the optimal size for securing the vessel deforming component to the aorta. Further, another difficulty relates to affixing the fastening components to the wrap. Attempting to hold the wrap in position around the aorta while securing the wrap in that position in a permanent fashion can be very difficult to accomplish with two hands.
There is a need in the art for an improved wrap and improved methods of securing that wrap to the target vessel.